“I don’t know what to eat anymore because the ‘experts’ keep changing their minds about what’s good for me…” It’s a common refrain, and a convenient one if you’re trying to justify a lousy diet, says one leading nutrition researcher. But it’s also plain wrong. We basically know what to do, he says, we just don’t do it.

David Katz MD, MPH, FACPM, FACP, FACLM, is the founding director of Yale University's Yale-Griffin Prevention Research Center, and president of the American College of Lifestyle Medicine. Speaking at the reThink Food​​ conference in Napa Valley, he said: “Knowledge, alas, isn’t always power. ​

“The problem is translating knowledge into action. We already know that lifestyle is the best medicine, the question is how do we get the medicine down?”​

While the conversation around dietary fats has become more nuanced, and there are scores of self-proclaimed experts and diet books telling us to eat more or less fat, carbs or proteins, return to the Paleolithic era, or ditch grains, the fundamentals of public health advice really haven’t changed, said Dr Katz.

It’s not as if when we were told to eat less saturated fat that we all started eating more beans and lentils instead of meat​

He explained: “If people stay confused about what a healthy diet is, you can keep selling the next and the next and the next diet book. And our culture has been making a ton of money out of sowing confusion, while the food industry has been exploiting the messages of experts and turning them into nonsense. ​

“So it’s not as if when we were told to eat less saturated fat that we all started eating more beans and lentils instead of meat; we just started eating low fat junk food. And when we didn’t get thin and healthy, we blamed it on cutting fat, instead of eating junk. ​

“And instead of learning from this [with carbs], we repeated that and started eating low carb junk food, and then gluten-free junk food."​

If people stay confused about what a healthy diet is, you can keep selling the next diet book​

He added: "Actually it’s remarkable how much consensus there is about the fundamentals of healthy eating... diets that emphasize vegetables, fruits, whole grains, nuts and seeds, beans, lentils, water for thirst, and food that’s minimally processed.”​

Epidemiological data, he says, consistently shows that avoiding tobacco, excessive stress and too much alcohol, refined carbohydrates and added sugar, and in turn eating more fruits, vegetables, whole grains and exercising more, is the secret to a longer, healthier life.

“These findings have been reaffirmed again and again. The fundamentals are there. Now we refine them of course; [for example] we know a lot more now about the differential effects of different types of fat.”​

Personalized nutrition is the icing on the cake​

While personalized nutrition is an exciting new field of research, it’s really the icing on the cake when it comes to deciding what to eat, although we're learning more all the time about the interplay between diet and genes, he said.

"The science is early and evolving but I do think there is real value there. The fundamentals of a health-promoting diet for our species are common to us all... but the customization is the icing on the cake."​

Personalized advice could also prove far more impactful than generic public health advice, he said: “Advice that’s unique to you is more motivating.”​

Dr Katz caught up with FoodNavigator-USA editor Elaine Watson at reThink Food​​, a three-day conference organized by the MIT Media Lab and the Culinary Institute of America, on Nov 4-6.

“It’s not as if when we were told to eat less saturated fat that we all started eating more beans and lentils instead of meat, we just started eating low fat junk food. And when we didn’t get thin and healthy, we blamed it on cutting fat, instead of eating junk. And then instead of learning from that, we repeated it [with carbs] and we started eating low carb junk food, and then gluten-free junk food."​​

2 comments

Does Food Navigator want to host a debate?

Posted by Richard David Feinman,
08 November 2016 - 17:18 GMT

I gave David a hard time in the previous comment because he was putting words i other people's mouths. The lines have been drawn for decades between low fat and low carbohydrate as the main generalization for therapy and to some extent for prevention. The failure of low fat has led to "slouching toward low carb" and the cop-out of "healthy fats." so there has been change but there is still much confusion. If Food Navigator would like, I know that David and I could provide a collegial and informative discussion.

We don't keep changing our minds -we still disagree.

We have had tremendous differences and one opinion that I hold to is that David Katz is not knowledgable, is not an expert on anything. That's disagreement.

It's not the media, it's not the people don't follow general agreement. The USDA guidelines, since inception have been narrow minded, unscientific. I could actually find some agreement that on of our problems is arrogant guys like this who have limited knowledge. I could should you some agreement there.